[BUG] The data of Master section should be exported with content page template

• Type: Technical Task
• Status: Closed
• Priority: Minor
• Resolution: Won't Fix
• Affects Version/s: None
• Fix Version/s: None
• Component/s: Page Templates
• Labels: None
• Sprint: S01E04 - Turtles Swamp, S01E05 - Flowers Rebellion, S01E06 - Trip to Canada

Step to reproduce:

1. Site admin > Site Builder > Page Templates > Page Templates tab
2. Add a new collection
3. Add a content page template and Publish
4. Export the content page template
5. Unzip
6. Open page-definition.json file

Expected Results:
The data of Master section should be in the file.

Actual Results:
The data of Master section isn't in the file.

Reproduced on:
Tomcat 9.0.17 + MySQL 5.7. Portal master GIT ID: 7f932aced830a9ecea8b1e55178226829708d762.